Targeted Disruption of Mouse Dip2B Leads to Abnormal Lung Development and Prenatal Lethality

Abstract

Molecular and anatomical functions of mammalian Dip2 family members (Dip2A, Dip2B and Dip2C) during organogenesis are largely unknown. Here, we explored the indispensable role of Dip2B in mouse lung development. Using a LacZ reporter, we explored Dip2B expression during embryogenesis. This study shows that Dip2B expression is widely distributed in various neuronal, myocardial, endothelial, and epithelial cell types during embryogenesis. Target disruption of Dip2b leads to intrauterine growth restriction, defective lung formation and perinatal mortality. Dip2B is crucial for late lung maturation rather than early-branching morphogenesis. The morphological analysis shows that Dip2b loss leads to disrupted air sac formation, interstitium septation and increased cellularity. In BrdU incorporation assay, it is shown that Dip2b loss results in increased cell proliferation at the saccular stage of lung development. RNA-seq analysis reveals that 1431 genes are affected in Dip2b deficient lungs at E18.5 gestation age. Gene ontology analysis indicates cell cycle-related genes are upregulated and immune system related genes are downregulated. KEGG analysis identifies oxidative phosphorylation as the most overrepresented pathways along with the G2/M phase transition pathway. Loss of Dip2b de-represses the expression of alveolar type I and type II molecular markers. Altogether, the study demonstrates an important role of Dip2B in lung maturation and survival.

Analysis of Dip2B Expression in Adult Mouse Tissues Using the LacZ Reporter Gene

“…LacZ expression was also detected in the prostate gland, oocytes, kidneys, adrenal glands, and intestinal glands. Cytological investigations are ongoing to identify the cell type-specific distribution of Dip2b gene expression and to elucidate possible functions of the Dip2b gene in these organs [16,25].…”

“…Recently, we reported that Dip2B is widely expressed during embryogenesis and its loss leads to prenatal lethality, possibly due to abnormal lung development [16]. In the present study, we aimed to delineate, in detail, the tissues that may require Dip2B in adults by characterizing and analyzing the expression of Dip2B using Dip2b tm1a(wtsi)komp (Dip2b Tm1a ) knock-in mice generated by the Knockout Mouse Project (KOMP) [17].…”

Kub3 Deficiency Causes Aberrant Late Embryonic Lung Development in Mice by the FGF Signaling Pathway

“…Embryonic lung tissue attached to the trachea was taken out, washed in PBS and placed into PBS buffer, and the floatation of the lungs was observed [ 43 ]. For the trachea Alcian blue–alizarin staining, lung tissues with trachea were washed with PBS and fixed in 20% ethanol; then, and the samples were rinsed in water, incubated in Alcian blue dye for 15 min, and then washed in running water.…”

DIP2 is a unique regulator of diacylglycerol lipid homeostasis in eukaryotes

“…Recently, a loss of virulence has been reported when FAAL-like domain (FLD)-containing protein, CPS1, a DIP2 orthologue, is mutated in either plant pathogenic fungi, which causes rice blast and wheat head scab, or human pathogenic fungus, that cause valley fever ( Lu et al, 2003 ; Narra et al, 2016 ; Wang et al, 2016 ). Furthermore, DIP2 has been shown to be crucial for axonal branching, neurite sprouting, and dendritic spine morphogenesis in Drosophila , Caenorhabditis elegans , and mice, respectively ( Ma et al, 2019a ; Ma et al, 2019b ; Sah et al, 2020 ; Ma et al, 2019a ; Nitta et al, 2017 ; Noblett et al, 2019 ; Xing et al, 2020 ). Three paralogues of DIP2 in humans have been implicated as a potential risk factor for neurodevelopmental disorders like autism spectrum disorders (ASDs) and other diseases ( Egger et al, 2014 ; Gong et al, 2018 ; Iossifov et al, 2012 ; Jiao et al, 2012 ; Kong et al, 2016 ; Poelmans et al, 2009 ; Rudin et al, 2012 ; Larsson et al, 2017 ; Supplementary file 1 ).…”